金回折格子構造による電流検出型SPR化学量センサの製作

抄録

This paper reports a current-sensing surface plasmon resonance (SPR) detector that operates in pure water using perpendicular incidence of light. The SPR detector has a gold diffraction grating on n-Si. The absorbed photon energy is converted into photocurrent by the Schottky barrier formed at the Au/n-Si interface, and can be detected as photocurrent. Using simulations, we searched for a grating structure that shows efficient light absorption in the near-infrared region. Based on the simulation, we fabricated the device and measured its reflectance and photoresponse against perpendicular incidence of light. The reflectance measurement showed similar spectrum as simulated. In the photocurrent detection experiment, photocurrent was generated at a wavelength of 1100 nm. Therefore, it was verified that the device can induce SPR and detect photocurrent by perpendicular incidence in the near-infrared region.